Toulon are determined to re-sign New Zealand centre Sonny Bill Williams after next year's World Cup.

The 24-year-old centre has made a dramatic impact on New Zealand rugby after moving from Toulon in the summer, starring for Canterbury in the ITM Cup and the All Blacks during their Gland Slam winning end-of-season tour of Britain and Ireland.

Toulon owner Mourad Boudjellal invited Williams to watch his side beat Montpellier 29-13 on Friday and made no secret of his desire to see the centre return to the club.

''Toulon is his home,'' he told reporters. ''[Williams] knows that this is his home and he misses the environment in Toulon. He is the one who'll decide on his future after the World Cup, but he has already proved that he can do the impossible on the rugby field.''

Williams was in Paris on promotional duty for the All Blacks along with Dan Carter, who is also attracting interest from European clubs with less than 10 months until the World Cup. And Carter indicated that he is open to offers post World Cup.

"The decision is whether to play in France, England or remain in New Zealand," said Carter. "I love New Zealand and enjoy playing at home, but all of these options are still possible. I'm going to ... make a decision next year.''

Boudjellal has indicated that Carter could be too expensive for the French club, particularly as the Toulon owner is hopeful of retaining the services of Jonny Wilkinson despite the RFU's desire to see England players return to the domestic game if they are to be considered for international duty after the World Cup.

''This isn't really a problem because they [RFU] specify that this decision will be applied except in exceptional circumstances,'' said Boudjellal.